How to grow walnuts?

1. Seed selection: select a tree (30-50 years old) with strong growth, no pests and diseases and full seeds as the mother tree for seed collection. When the green peel of nuts turns from green to yellow and cracks, they can be harvested. In order to ensure the quality of seeds, seed walnuts should be harvested 3-5 days later than commercial walnuts. Autumn-sown walnuts can be sown with green skins, while spring-sown walnuts need to be peeled, dried and stored.

Second, seed treatment: autumn seeds can be sown directly without any treatment. When sowing in spring, soak the seeds before sowing to ensure germination. Commonly used methods are as follows:

1, cold water immersion method. Soak in cold water for 7- 10 days, change the water once a day, or put the sacks filled with walnut kernels into flowing water to make them absorb water, expand and crack, and then sow.

2. Warm water immersion method. Put the seeds in a warm water tank at 80℃, and then stir them continuously to cool them naturally to normal temperature. Soak for 8- 10 days, change water every day, and take out the seeds for sowing after they burst.

Third, sow.

1, sowing date: autumn sowing and spring sowing. Autumn sowing should be carried out before soil freezing (65438+1late October-165438+1late October). Spring sowing should be carried out immediately after soil thawing (mid-March-early April).

2. Seeding method: First, make a seedbed with the width of 1m, and sow 2-3 rows in each bed with the row spacing of 20-30cm and the plant spacing of 10- 15cm. The sowing method is that the seed suture line is vertical to the ground, and the seed tip is biased to one side, which is beneficial to seedling emergence; Cover the soil with 5- 10 cm after sowing.

Fourth, fertilization:

1, base fertilizer. The base fertilizer should be applied as soon as possible and should be completed after harvest and before defoliation. Each adult tree should be applied with high-quality organic fertilizer 100 ~ 200 kg.

2. Top dressing. The suitable period of topdressing is three stages: before flowering, young fruit expansion and fruit hard core. Generally, 0.8 ~ 1 kg of nitrogenous phosphate fertilizer is applied to each plant every time.

3. Spraying fertilizer on the leaves. Fertilization period is flowering period, new shoot growth period, flower bud differentiation period and after harvest. Commonly used fertilizer spraying types are 0. 1% ~ 0.2% boric acid, 0.5% ~ 1% ammonium molybdate and 0.3% ~ 0.4% copper sulfate.

V. Disease prevention:

1, walnut branch blight: this disease is a fungal disease. It mainly harms the branches and causes them to die. The damage rate of plants is generally around 20%, and it can reach 90% in severe cases. This disease mainly affects the growth and yield of trees.

The symptom of the disease is that after the 1-2-year-old branches are damaged, they gradually dry from the top to the trunk, and the leaves turn yellow and fall off. Dense black spots are produced on the dead branches, and mucus flows out when the humidity is high, forming black tumor-like protrusions. Bacteria overwinter on diseased branches and invade through wounds, only hurting weak trees.

2. Pests: Leaf-eating pests, such as aphids and moths.

Prevention and control methods: destruction, removal of diseased branches and centralized incineration. Drugs, control time and chemicals used are the same as the control of walnut anthracnose.

Extended data:

Another method of walnut propagation and seedling raising: grafting

Steps:

1, the rootstock is this rootstock or walnut 1 ~ 2-year-old seedlings.

2. Stack the seed sand storehouse for more than 60 days, and then take it out for sowing in spring.

3. The row spacing of drilling holes is 30 ~ 40cm, the plant spacing is12 ~15cm, and the covering soil is about 5cm. When sowing, the suture line of the seed is perpendicular to the ground, which is beneficial to the smooth growth of radicle and bud.

4. The suitable time for grafting is between beginning of spring and rainy season, and the best time is when the juice begins to flow out and the terminal bud of the rootstock has sprouted.

5. The suitable time for bud grafting is around the vernal equinox, when the rootstock begins to sprout, the top bud spreads its leaves and the bark is easy to peel off.

6. After grafting, the interface and scion were covered with plastic bags and wrapped with wet sawdust for insulation, and the grafting survival rate was over 95%.

7. Grafting of walnut cotyledon seedlings. When the seed buds will expose the true leaves, cut off the rootstock buds on the petiole 1 cm, and then put them into a healing pool or a simple greenhouse. Transplanted into the field after survival, the survival rate is over 80%, which can shorten the seedling raising time.

References:

Baidu encyclopedia-walnut

Baidu encyclopedia-walnut